In-circuit emulators and logic analyzers are often used with programmable logic devices in testing and debugging circuits. Testing and debugging generally entails running the circuit, applying input stimuli, and checking the states of selected signals in the circuit.
In one approach, a programmable integrated circuit includes programmable logic and interconnect resources that are configured to implement the circuit-under-test and a trigger-and-capture circuit. The trigger-and-capture circuit receives signals from the circuit-under-test. The signals include trigger signals and data signals. The trigger signals are used to control the initiation of gathering states of the data signals. The states of the data signals are continuously logged into the on-chip memory of the programmable integrated circuit. The sampled data is then sent to a host computer system via a boundary scan interface that is connected to the on-chip memory. Software executing on the host computer system displays the sampled data and provides a mechanism to adjust the trigger condition via the boundary scan interface.
One or more embodiments enhance testability of circuits.